One of my favorite quilt shops had totes where customers could pick fabrics from and were sold by the pound. Since current events they now sell them online as pound packages and each package includes is assorted by color or theme blues, yellows etc. . Another shop used to sell just by the box, and you never knew what you’d get, sometimes it might have 2 yards of a fabric down to a fat eighth, I was always happy with what I got.
I think it all depends on how much time and effort you want to put into the project and how you plan to sell everything. If you are doing it via garage sale? I would sell it by the pound for anything less than 1/2 yard and perhaps sort everything by color and/or theme and let people pick and choose. If your setting up on eBay or Etsy then you might want to spend more time sorting and categorizing as people tend to want to see what they are getting, online selling is tedious. You might want to take a look on both sites and see what others are doing. I would not spend the time to cleanup edges way too much effort IMHO.
Now, if you want to really get into everything and spend the time you can cut and make your own precuts and bundle accordingly from Mini Charms up to FQ Bundles and see how they sell.
Good luck, its no easy task, perhaps you can enlist the help of family and friends to help?